Efficacy of pharmacological therapies for preventing post-dural puncture headaches in obstetric patients: a Bayesian network meta-analysis of randomized controlled trials

Background Post-dural puncture headache (PDPH) is a major complication of neuraxial anesthesia. PDPH usually occurs after Caesarean section in obstetric patients. The efficacy of prophylactic pharmacological therapies remains controversial. Methods Seven pharmacological therapies (aminophylline (AMP), dexamethasone, gabapentin/pregabalin (GBP/PGB), hydrocortisone, magnesium, ondansetron (OND), and propofol (PPF)), were studied in this Bayesian network meta-analysis. The primary outcome was the cumulative incidence of PDPH within 7 days. Secondary outcomes included the incidence of PDPH at 24 and 48 h postoperatively, the severity of headache in PDPH patients (24, 48, and 72 h postoperatively), and postoperative nausea and vomiting (PONV). Results Twenty-two randomized controlled trials with 4,921 pregnant women (2,723 parturients received prophylactic pharmacological therapies) were included. The analyses demonstrated that PPF, OND, and AMP were efficient in decreasing the cumulative incidence of PDPH during the follow-up period compared to the placebo group (OR = 0.19, 95% CI: 0.05 to 0.70; OR = 0.37, 95% CI: 0.16 to 0.87; OR = 0.40, 95% CI: 0.18 to 0.84, respectively). PPF and OND had the lower incidence of PONV compared to the placebo group (OR = 0.07, 95% CI: 0.01 to 0.30; and OR = 0.12, 95% CI: 0.02 to 0.63). No significant difference in other outcomes was found among different therapies. Conclusions Based on available data, PPF, OND, and AMP may have better efficacy in decreasing the incidence of PDPH compared to the placebo group. No significant side effects were revealed. Better-designed studies are requested to verify these conclusions. Supplementary Information The online version contains supplementary material available at 10.1186/s12884-023-05531-7.


Rationale
3 Describe the rationale for the review in the context of what is already known, including mention of why a network meta-analysis has been conducted.

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Objectives 4 Provide an explicit statement of questions being addressed, with reference to participants, interventions, comparisons, outcomes, and study design (PICOS).

Protocol and registration 5
Indicate whether a review protocol exists and if and where it can be accessed (e.g., Web address); and, if available, provide registration information, including registration number.

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Eligibility criteria 6 Specify study characteristics (e.g., PICOS, length of follow-up) and report characteristics (e.g., years considered, language, publication status) used as criteria for eligibility, giving rationale. Clearly describe eligible treatments included in the treatment network, and note whether any have been clustered or merged into the same node (with justification).

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Information sources 7 Describe all information sources (e.g., databases with dates of coverage, contact with study authors to identify additional studies) in the search and date last searched.

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Search 8 Present full electronic search strategy for at least one database, including any limits used, such that it could be repeated. 6 Study selection 9 State the process for selecting studies (i.e., screening, eligibility, included in systematic review, and, if applicable, included in the meta-analysis).

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Data collection process 10 Describe method of data extraction from reports (e.g., piloted forms, independently, in duplicate) and any processes for obtaining and confirming data from investigators.

Data items 11
List and define all variables for which data were sought (e.g., PICOS, funding sources) and any assumptions and simplifications made. 6 Geometry of the network S1 Describe methods used to explore the geometry of the treatment network under study and potential biases related to it. This should include how the evidence base has been graphically summarized for presentation, and what characteristics were compiled and used to describe the evidence base to readers.

Risk of bias within individual studies 12
Describe methods used for assessing risk of bias of individual studies (including specification of whether this was done at the study or outcome level), and how this information is to be used in any data synthesis.

RESULTS † Study selection 17
Give numbers of studies screened, assessed for eligibility, and included in the review, with reasons for exclusions at each stage, ideally with a flow diagram.

Presentation of network structure S3
Provide a network graph of the included studies to enable visualization of the geometry of the treatment network.

Supplement al file Summary of network geometry S4
Provide a brief overview of characteristics of the treatment network. This may include commentary on the abundance of trials and randomized patients for the different interventions and pairwise comparisons in the network, gaps of evidence in the treatment network, and potential biases reflected by the network structure.

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Study characteristics 18 For each study, present characteristics for which data were extracted (e.g., study size, PICOS, follow-up period) and provide the citations.

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Risk of bias within studies 19 Present data on risk of bias of each study and, if available, any outcome level assessment.

Results of individual studies 20
For all outcomes considered (benefits or harms), present, for each study: 1) simple summary data for each intervention group, and 2) effect estimates and confidence intervals. Modified approaches may be needed to deal with information from larger networks.

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Synthesis of results 21 Present results of each meta-analysis done, including confidence/credible intervals. In larger networks, authors may focus on comparisons versus a particular comparator (e.g. placebo or standard care), with full findings presented in an appendix. League tables and forest plots may be considered to summarize pairwise comparisons. If additional summary measures were explored (such as treatment rankings), these should also be presented.

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Exploration for inconsistency S5 Supplement al file Risk of bias across studies 22 Present results of any assessment of risk of bias across studies for the evidence base being studied. 9 Results of additional analyses 23 Give results of additional analyses, if done (e.g., sensitivity or subgroup analyses, meta-regression analyses, alternative network geometries studied, alternative choice of prior distributions for Bayesian analyses, and so forth).

Summary of evidence 24
Summarize the main findings, including the strength of evidence for each main outcome; consider their relevance to key groups (e.g., healthcare providers, users, and policy-makers).

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Limitations 25 Discuss limitations at study and outcome level (e.g., risk of bias), and at review level (e.g., incomplete retrieval of identified research, reporting bias). Comment on the validity of the assumptions, such as transitivity and consistency. Comment on any concerns regarding network geometry (e.g., avoidance of certain comparisons).

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Conclusions 26 Provide a general interpretation of the results in the context of other evidence, and implications for future research.

FUNDING
Funding 27 Describe sources of funding for the systematic review and other support (e.g., supply of data); role of funders for the systematic review. This should also include information regarding whether funding has been received from manufacturers of treatments in the network and/or whether some of the authors are content experts with professional conflicts of interest that could affect use of treatments in the network.

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PICOS = population, intervention, comparators, outcomes, study design. † Authors may wish to plan for use of appendices to present all relevant information in full detail for items in this section.